For some reason the supports I had snapped off the base a few years ago, and I just have them sitting in a box with a few other extraneous parts.
I think they just sit on the valve covers IIRC, so the design purpose must have been to keep the base from hitting anything beneath it, such as distributor caps, coils, etc.
BTW, Racer57, did you purchase your 70 from Broward county Florida?
I test drove one very much like yours 5 years ago. It was a 383 4 barrel also. No wing or shaker though, my favorite color.